68.4: Optical Properties of Visible-Light Excited Phosphor Sheet (VEPS) System

The optical properties in Visible-light Excited Phosphor Sheet (VEPS) system were discussed and calculated. Different to the conventional LED backlight with white LEDs, VEPS system applies blue LED chips to excite the extrinsic flat YAG-phosphor layer to perform uniform and flat lighting, that can further reduce the backlight thickness. A theoretical model was developed to optimize the structure of VEPS system. Consequently, the optimized result was demonstrated on the small-sized VEPS module.